1. Field of the Invention
The present invention relates to a hand shake correction apparatus and a digital image photographing apparatus including the same. More particularly, the present invention relates to a hand shake correction apparatus that reduces image blurring caused by a user's hand shaking when photographing an image using a digital photographing device, and a digital photographing apparatus including the hand shake correction apparatus.
2. Description of the Related Art
Generally, a digital photographing apparatus is an apparatus that generates and/or stores digital files of still or moving images. Examples of such a digital photographing apparatus include a digital still camera (DSC), a digital video camera (DVC), digital cameras installed in mobile phones, and the like.
Because a large number of such digital photographing apparatuses are in use in current times, consumers are increasingly demanding products that provide high quality still images and/or moving images. As a result, demands are increasing for digital photographing apparatuses that include a hand shake correction apparatus for preventing decrease in clarity of images which may be caused due to a user's hand shaking while using the digital photographing apparatus. A conventional hand shake correction apparatus performs a hand shake correction function by moving a hand shake correction lens or an imaging device. FIG. 1 is a view illustrating an example of a portion of a conventional hand shake correction apparatus which performs a hand shake prevention functionality by moving a hand shake correction lens.
Referring to FIG. 1, the conventional hand shake correction apparatus includes a correction lens supporting plate 13 supporting a correction lens (not shown), and a base 20 supporting the correction lens supporting plate 13 to be movable along a plane. In FIG. 1, a correction lens (not shown) is inserted into an opening portion of the correction lens supporting plate 13. In order to move the correction lens supporting plate 13 with respect to the base 20, a first driving unit 31 moving the correction lens supporting plate 13 in a first direction and a second driving unit 32 moving the correction lens supporting plate 13 in a second direction are disposed on the correction lens supporting plate 13. Also, a first detecting unit 41 and a second detecting unit 42, which are disposed on the correction lens supporting plate 13, detect how much the correction lens and/or the correction lens supporting plate 13 are moved with respect to the base 20.
When the conventional hand shake correction apparatus is installed in a digital photographing apparatus, the base 20 is installed in a body of the digital photographing apparatus, and even when the base 20 of the hand shake correction apparatus is shaken due to the body of the digital photographing apparatus being shaken due to hand shake, etc., the correction lens supporting plate 13 is moved relative to the base 20 together with the correction lens, and consequently, light that has passed through other lens portions including the correction lens is incident on predetermined portions of the imaging device despite the shaking of the digital photographing apparatus. Accordingly, a clear still or moving image without blur can be obtained.
The conventional hand shake correction apparatus illustrated in FIG. 1 is a shutter integrated hand shake correction apparatus in which a shutter 51 and a shutter driving unit 53 are integrally formed in the hand shake correction apparatus. Accordingly, in order to arrange the shutter 51 and the shutter driving unit 53, the shape of the correction lens supporting plate 13 is not symmetric about a crossing point COA of the correction lens and the optical axis passing through the correction lens, which can be regarded as the center of the hand shake correction apparatus, as illustrated in FIG. 1. As a result, a center of mass CM of a correction lens module including the correction lens and the correction lens supporting plate 13 is deviated from the optical axis passing through the crossing point COA of the correction lens and the optical axis passing through the correction lens. Accordingly, a center of force CF, which is the crossing point of a driving force action line FV of the first driving unit 31 moving the correction lens supporting plate 13 in a first direction and a driving force action line FH of the second driving unit 32 moving the correction lens supporting plate 13 in a second direction, does not correspond to the center of mass CM of the correction lens module. Thus, torque is generated when the correction lens module is moved by the first driving unit 31 and the second driving unit 32. As undesired torque is generated as described above when the hand shake correction apparatus is being operated, the hand shake prevention function of the hand shake correction apparatus is degraded.
Further, as illustrated in FIG. 1, the center of force CF, which is the crossing point of the driving force action line FV of the first driving unit 31 and the driving force action line FH of the second driving unit 32, does not correspond to the crossing point COA of the correction lens and the optical axis passing through the correction lens, either, which can be regarded as the center of the hand shake correction apparatus. Accordingly, in FIG. 2, which is a view illustrating an example of a portion of another conventional hand shake correction apparatus, the positions of the first driving unit 31 and the first detecting unit 41 are switched, and the positions of the second driving unit 32 and the second detecting unit 42 are switched in order that the center of force CF, which is the crossing point of the driving force action line FV of the first driving unit 31 and the driving force action line FH of the second driving unit 32, coincides with the crossing point COA of the correction lens and the optical axis passing through the correction lens, which can be regarded as the center of the hand shake correction apparatus.
However, although the first and second driving units 31 and 32 are illustrated to be small for convenience of illustration in FIGS. 1 and 2, the actual size of the first and second driving units 31 and 32 is large, and thus it is not easy to arrange them as illustrated in FIG. 2. Furthermore, as illustrated in FIG. 2, since the first detecting unit 41 and/or the second detecting unit 42 are disposed to be more adjacent to the shutter driving unit 53 than they are in FIG. 1, they may be affected by the shutter driving unit 53 and thus the movement of the correction lens supporting plate 13 may not be accurately detected.